Oh, Lou, we all understand believe me. The recommendation is servicing annually or at least every 18 months. Please don't tell my machine!
Mine is even pricier to clean here, as it has an embroidery module which must be serviced at the same time. The machine was bought on sale for $295, down from $395. The "annual" service locally runs $150. If it were just the sewing machine it would be $110. In the UK that's 223 instead of 298 with the service being 113 or 83 for just a machine. I'm trying to figure out how to add the UK pound symbol but it didn't work.
So my machine has not been in. I don't sew a great deal, don't sew any challenging heavy fabrics, keep it in a case and keep it cleaned out. New needle every project or two depending on size, good quality thread, every bobbin change I clean out the raceway and remove all the lint and bits. I also sew "properly", never going over pins or pulling on the fabric.
If I had an expensive machine or sewed weekly with it I would absolutely take it in regularly. I'm thinking maybe in January or February next year. Serger ought to go in with it. I'll clean house or something while they're gone.